ch := d.Cache[h.String()].Children
	res := make(dataUsageHashMap, len(ch))
	for k := range ch {
		res[k] = struct{}{}
	}
	return res
}

// searchParent will search for the parent of h.
// This is an O(N*N) operation if there is no parent or it cannot be guessed.
func (d *dataUsageCache) searchParent(h dataUsageHash) *dataUsageHash {
	want := h.Key()